diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/check_mtu.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/check_mtu.c b/tools/testing/selftests/bpf/prog_tests/check_mtu.c new file mode 100644 index 000000000000..36af1c138faf --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/check_mtu.c @@ -0,0 +1,216 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Jesper Dangaard Brouer */ + +#include <linux/if_link.h> /* before test_progs.h, avoid bpf_util.h redefines */ +#include <test_progs.h> +#include "test_check_mtu.skel.h" +#include "network_helpers.h" + +#include <stdlib.h> +#include <inttypes.h> + +#define IFINDEX_LO 1 + +static __u32 duration; /* Hint: needed for CHECK macro */ + +static int read_mtu_device_lo(void) +{ + const char *filename = "/sys/class/net/lo/mtu"; + char buf[11] = {}; + int value, n, fd; + + fd = open(filename, 0, O_RDONLY); + if (fd == -1) + return -1; + + n = read(fd, buf, sizeof(buf)); + close(fd); + + if (n == -1) + return -2; + + value = strtoimax(buf, NULL, 10); + if (errno == ERANGE) + return -3; + + return value; +} + +static void test_check_mtu_xdp_attach(void) +{ + struct bpf_link_info link_info; + __u32 link_info_len = sizeof(link_info); + struct test_check_mtu *skel; + struct bpf_program *prog; + struct bpf_link *link; + int err = 0; + int fd; + + skel = test_check_mtu__open_and_load(); + if (CHECK(!skel, "open and load skel", "failed")) + return; /* Exit if e.g. helper unknown to kernel */ + + prog = skel->progs.xdp_use_helper_basic; + + link = bpf_program__attach_xdp(prog, IFINDEX_LO); + if (CHECK(IS_ERR(link), "link_attach", "failed: %ld\n", PTR_ERR(link))) + goto out; + skel->links.xdp_use_helper_basic = link; + + memset(&link_info, 0, sizeof(link_info)); + fd = bpf_link__fd(link); + err = bpf_obj_get_info_by_fd(fd, &link_info, &link_info_len); + if (CHECK(err, "link_info", "failed: %d\n", err)) + goto out; + + CHECK(link_info.type != BPF_LINK_TYPE_XDP, "link_type", + "got %u != exp %u\n", link_info.type, BPF_LINK_TYPE_XDP); + CHECK(link_info.xdp.ifindex != IFINDEX_LO, "link_ifindex", + "got %u != exp %u\n", link_info.xdp.ifindex, IFINDEX_LO); + + err = bpf_link__detach(link); + CHECK(err, "link_detach", "failed %d\n", err); + +out: + test_check_mtu__destroy(skel); +} + +static void test_check_mtu_run_xdp(struct test_check_mtu *skel, + struct bpf_program *prog, + __u32 mtu_expect) +{ + const char *prog_name = bpf_program__name(prog); + int retval_expect = XDP_PASS; + __u32 mtu_result = 0; + char buf[256] = {}; + int err; + struct bpf_prog_test_run_attr tattr = { + .repeat = 1, + .data_in = &pkt_v4, + .data_size_in = sizeof(pkt_v4), + .data_out = buf, + .data_size_out = sizeof(buf), + .prog_fd = bpf_program__fd(prog), + }; + + err = bpf_prog_test_run_xattr(&tattr); + CHECK_ATTR(err != 0, "bpf_prog_test_run", + "prog_name:%s (err %d errno %d retval %d)\n", + prog_name, err, errno, tattr.retval); + + CHECK(tattr.retval != retval_expect, "retval", + "progname:%s unexpected retval=%d expected=%d\n", + prog_name, tattr.retval, retval_expect); + + /* Extract MTU that BPF-prog got */ + mtu_result = skel->bss->global_bpf_mtu_xdp; + ASSERT_EQ(mtu_result, mtu_expect, "MTU-compare-user"); +} + + +static void test_check_mtu_xdp(__u32 mtu, __u32 ifindex) +{ + struct test_check_mtu *skel; + int err; + + skel = test_check_mtu__open(); + if (CHECK(!skel, "skel_open", "failed")) + return; + + /* Update "constants" in BPF-prog *BEFORE* libbpf load */ + skel->rodata->GLOBAL_USER_MTU = mtu; + skel->rodata->GLOBAL_USER_IFINDEX = ifindex; + + err = test_check_mtu__load(skel); + if (CHECK(err, "skel_load", "failed: %d\n", err)) + goto cleanup; + + test_check_mtu_run_xdp(skel, skel->progs.xdp_use_helper, mtu); + test_check_mtu_run_xdp(skel, skel->progs.xdp_exceed_mtu, mtu); + test_check_mtu_run_xdp(skel, skel->progs.xdp_minus_delta, mtu); + +cleanup: + test_check_mtu__destroy(skel); +} + +static void test_check_mtu_run_tc(struct test_check_mtu *skel, + struct bpf_program *prog, + __u32 mtu_expect) +{ + const char *prog_name = bpf_program__name(prog); + int retval_expect = BPF_OK; + __u32 mtu_result = 0; + char buf[256] = {}; + int err; + struct bpf_prog_test_run_attr tattr = { + .repeat = 1, + .data_in = &pkt_v4, + .data_size_in = sizeof(pkt_v4), + .data_out = buf, + .data_size_out = sizeof(buf), + .prog_fd = bpf_program__fd(prog), + }; + + err = bpf_prog_test_run_xattr(&tattr); + CHECK_ATTR(err != 0, "bpf_prog_test_run", + "prog_name:%s (err %d errno %d retval %d)\n", + prog_name, err, errno, tattr.retval); + + CHECK(tattr.retval != retval_expect, "retval", + "progname:%s unexpected retval=%d expected=%d\n", + prog_name, tattr.retval, retval_expect); + + /* Extract MTU that BPF-prog got */ + mtu_result = skel->bss->global_bpf_mtu_tc; + ASSERT_EQ(mtu_result, mtu_expect, "MTU-compare-user"); +} + + +static void test_check_mtu_tc(__u32 mtu, __u32 ifindex) +{ + struct test_check_mtu *skel; + int err; + + skel = test_check_mtu__open(); + if (CHECK(!skel, "skel_open", "failed")) + return; + + /* Update "constants" in BPF-prog *BEFORE* libbpf load */ + skel->rodata->GLOBAL_USER_MTU = mtu; + skel->rodata->GLOBAL_USER_IFINDEX = ifindex; + + err = test_check_mtu__load(skel); + if (CHECK(err, "skel_load", "failed: %d\n", err)) + goto cleanup; + + test_check_mtu_run_tc(skel, skel->progs.tc_use_helper, mtu); + test_check_mtu_run_tc(skel, skel->progs.tc_exceed_mtu, mtu); + test_check_mtu_run_tc(skel, skel->progs.tc_exceed_mtu_da, mtu); + test_check_mtu_run_tc(skel, skel->progs.tc_minus_delta, mtu); +cleanup: + test_check_mtu__destroy(skel); +} + +void test_check_mtu(void) +{ + __u32 mtu_lo; + + if (test__start_subtest("bpf_check_mtu XDP-attach")) + test_check_mtu_xdp_attach(); + + mtu_lo = read_mtu_device_lo(); + if (CHECK(mtu_lo < 0, "reading MTU value", "failed (err:%d)", mtu_lo)) + return; + + if (test__start_subtest("bpf_check_mtu XDP-run")) + test_check_mtu_xdp(mtu_lo, 0); + + if (test__start_subtest("bpf_check_mtu XDP-run ifindex-lookup")) + test_check_mtu_xdp(mtu_lo, IFINDEX_LO); + + if (test__start_subtest("bpf_check_mtu TC-run")) + test_check_mtu_tc(mtu_lo, 0); + + if (test__start_subtest("bpf_check_mtu TC-run ifindex-lookup")) + test_check_mtu_tc(mtu_lo, IFINDEX_LO); +} |